| 摘要 |
PURPOSE:To obtain a reduction gear which is small in size but can transmit great power while having a large reduction ratio, by using trochoidal tooth form curves for the tooth form of the gears of a fixed internal gear and a planetary external gear, and interposing a rolling body between said internal and external gears. CONSTITUTION:When an input rotation is provided to an input shaft 11, a disk 32, which is freely rotatingly linked to an eccentric shaft 12, revolves around the input shaft at the same speed ratio as the input rotation. A groove 42 having an epitrochoidal tooth form is provided on the disk 32, and is opposed to a groove 41 having a hypotrochoidal tooth form, which is fixed on a case 31. And, the movement of a ball 47 interposed between these grooves permits the disk 32 to carry out a rotating movement which is determined by the number of teeth of these grooves. Thereby, speed reduction can be carried out by taking out this rotation as an output. |
